V8 RX-7, who's done one?

Ok, for the second part in my V8 XXX, who's done one: I rode in my buddies LS3-equipped FD last week after helping him get the wiring sorted out. Man, what a car. Now, I just don't have the coinage for a LS powered FD, or an LS powered FC even. He's trying to get me to put a 5.3 in an FC. I like the RX-7 a lot but just can't do the LS. Would you do the 5.3, or a 5.0 Ford? What can you tell me about cost, driving impressions and what you would do differently if you did it again? Thanks.

For cheap, I strongly suggest a 5.0 Ford. Engine and transmission are available for decent money. Check out Granny's Speed Shop for the conversion kits. They say you can do it in a busy weekend. No welding, and if you use a carb'd engine, no problem with wiring. One of my unfulfilled fantasies. They do quite well in autocross, I understand, and embarrassing high buck cars is always fun. "Hey, I got 2010.00 in my car. How about you?" High performance parts are as close as a Mustang shops trash bin.

Can the stock rear end stay (it's still solid on an FC, right?)?

How about a 5.0 SA chassis? They are the lightest of them all,and if you ask me the best looking of the first gens with their steel bumpers. They are a bit on the unsophisticated side compared the FC,and FD,but still handle well,and are super simple cars.

Chris

Independent rear on the FC. If it is a turbo unit it should hold up to the thump of the V8.

you could always use the truck LS-based engine to do the swap then swap to an LS3 or whatnot later on when you get the cash.

The Ford 5.0L HO is cheap and a great engine, but the LS engines are a better starting point these days. The 5.0L engine is getting old and difficult to find a good used one that doesn't need to be rebuilt. If you had a spare one kicking around, I'd say use it.

You can generally pick up the 5.3L iron truck LS engines for around $500.

Mazdax605 wrote: Independent rear on the FC. If it is a turbo unit it should hold up to the thump of the V8.

The FC turbo rear end comes with beefier transmission, driveshafts, propshaft, and differential housing with a clutch-type LSD. IIRC, they are good for 500-550hp, but above that you will need to beef up the rear end more (like switching to a Ford 8.8 torque-arm assembly. Granny's sells the conversion kit, you supply the 8.8 from a Mustang or Exploder). The turbo parts swap readily into the non-turbo cars, which is good because all USDM FC Turbos were loaded from the factory (sunroof, P/S, P/W, etc.) while some non-turbos were available as stripped-out models. The lightest layout would be a 86-88 base model with a 5-lug conversion or a 86-88 Sport model, which is what my JDM 13BT-swapped RX-7 started life as.

Mine is a 1984 GSL-SE equipped 5.0 with a T5, I concentrated on lightness and a street car, I got it to 325hp, using aluminum heads, roller rockers, EFI Holley Systemax, BBW headers, lightened flywheel, T5 etc. Moved battery behind passenger seat, removed AC and kept weight within 20 lbs of stock.

Gained 3 x horsepower and 3 x torque

http://s869.photobucket.com/albums/ab256/aussiesmg/RX50/?action=view&current=007-1.mp4

In reply to aussiesmg:

sounds pretty darn sweet

In reply to aussiesmg:

(this is a hijacking of the thread, I am sorry)

You mean BBK headers? If so, what do you think of them? I am looking for a full exhaust for my Mustang and right now ceramic coated non-equal-length BBK shorties have my interest.

Oops, yep BBK ( what was on my mind ) and they are long tubes....

In reply to aussiesmg:

Ah, hrm, not really that close to what I'm thinking, which is BBK shorties backed up by a Magnaflow 50 state legal x-pipe (real 50 state cats! X-pipe!) and Dr. Gas Freq Mod mufflers all finished out with Cherry Bomb resonator tips.

AKA, a bunch of stuff you didn't use. Hrm.

RX-7 shells, 1 SBC drag car:

http://pittsburgh.craigslist.org/cto/2560286689.html

http://pittsburgh.craigslist.org/ctd/2510395403.html

http://pittsburgh.craigslist.org/cto/2540242133.html

http://pittsburgh.craigslist.org/cto/2473694729.html

I would recommend the 5.0 swap in the FB RX-7 or a 5.0 or 5.3 in the FC.

We have a 5.0 FB Lemons car. Very easy to work on.

Currently just starting a LS1 FB which should still have plenty of room. After selling the rotary I am only out $350 for the LS1/T56 and I think I can zero it out before spending again. Its false math since I had about $3500 from 2009 in the stuff I sold from it.

Interesting.

I really want to do an L-series V8, but I dont know if I can get the scratch together. Crap, my buddy was showing me LS1's that were $2500 and more, the T-56, another grand.
He's trying to sell me on the idea of the 5.3 truck motor, but I'm worried about two things, c.i.d. envy and having that iron lump our there on the front axle. I need to start looking at engine weights and such. What about an LT-1?

I thought the truck 5.3 was lighter then the 5.0. Maybe I am going crazy.

From what I have read the iron block adds about 60lbs or so over the aluminum.

For what its worth you can get the L33 (I think) which came in the SSR, Buick Rendezvous and others for less. I had found a 40k pull out on car-part for $650. You might still need the camarobird/vette accessories, oil pan and intake for clearance reasons. I have heard of complete iron block 4.8 and 5.3's going for as cheap as $300.

I went with the LS1/T56 because we made a deal at $2500 if I pulled it which also got me the wiring and some spares out of the car. By the time I bought the trans ($1000 - $2000) and got all the accessories and intake I would have been at the same money if not more and piecing everything together. If you can find a wrecked donor for $3500 or less you should be able to recoup a good deal of money back. You can find clean 2nd gen rollers for $1000 all day.

Most LT1's were iron block and heads aside from the vette I believe. I would go 5.3 at that point.

Greg Voth wrote: Most LT1's were iron block and heads aside from the vette I believe. I would go 5.3 at that point.

All LT1's have an iron block.

Only the Impala and Caprice versions have the iron heads. All F-bodies and Vette's came with AL heads.

That said the 5.3 LS is a better engine. I wouldn't bother with an LT1 unless it was silly cheap (like free). The the red headed stepchild of the Chevy small blocks. Good engine though, mine went well over 200k.

In reply to Soma007:

Thanks for clearing that up. I knew they were all iron block and knew the vettes were aluminum heads but didn't know the F-Bodys were as well.

Are you sure you don't want to just buy my 83 Sapporo,and put a V8 in it? You will be blazing a new trail,but that is the GRM way,right?

Chris

This thread made me attempt to Google for engine weights again. Always a frustrating experience. Something like the second search result was people here at GRM agreeing that it's always a frustrating experience.

Waiting for my standing CL search for a suitable hanging scale for my engine hoist. Then I just have to wait for every engine I'm interested in to wander past my garage...

In reply to ransom: Check out: http://www.norotors.com/index.php for an overload of RX-7 V/8 swaps. A lot of very nice cars.